Nicki is done because her last tour grossed less than 10 million, has had a bunch of flop songs in a row, her last album sold less than ARTPOP & her Dr. Luke produced lead single is the biggest flop lead single of the year so far + PnP video has way less views than G.U.Y.
Idk if she's done b/c she's a major sell-out who will do whatever it takes to claw her way to the top of the charts but the performance of PNP is kind of alarming.